Strip shearing attachment



Nov. 7, 1944. J, GA KlN 2,362,437

STRIP SHEARING ATTACHMENT Filed June 11, 1941 5 Sheets-Sheet 1 JOSEPH GALKIN mvENToR,

ATTORNEY.

' Nov. 7, 1-944. J. GALKIN- 2,362,437

STRIP SHEARING ATTACHMENT I Filed June 11, 1941 5 Sheets-Sheet 2 I MK JOSEPH GALKIN INVENTOR. 4

Nbv. 7, 1944. a. GALKIN} 2,362,437

. STRIP SHEARING ATTACHMENT Fi1ed.June 11, 1941 5 Sheets-Sheet 3 Nov. -7, 1944. q. GALKIN 2,362,437 swmr samme mncmwur v Filed .June 11, 1941 -5 Sheets-Sheet '4' I l l m 4) 0 0 ,1

JOSEPH GALK IN F INVENTOR.

' ATTORNEY Nov. 7, 1944. J. GALKIN STRIP SHEARING ATTACHMENT Filed June 11, 1941 5 Sheets-Sheet 5 JO5EPH GALKIN INVENTOR. BYW M ATTORNEY.

Patented Nov. 7, 1944 UNITED STATES PATENT osrlcs STRIP SHEARING ATTACHMENT Joseph Galkin, New York, N. Y.

Application June 11, 1941, Serial No. 397,529

This invention relates to a strip cutting mech- 2 Claims.

anism adapted for application to a sewing machine for making stitched belt loop strip material, and whereby the strip is cut into predetermined lengths.

An object of this invention is to provide a strip cutting mechanism driven by the main shaft of the sewing machine and having a pivotally mounted shear blade which is held in open position by a spring-actuated lever, and to provide a cam fixed to the shaft of the said mechanism for quickly actuating and quickly releasing the said lever andshear blade so as to permit continuous feeding of the strip without interruption by the shear and without exerting undue pres sure on the sewing machine mechanism.

Another object of this invention is to provide a shifting lever for at will shifting the lever out of engagement with the cam during operation of the machine, to permit a spring acting upon the lever to yieldingly hold the movable shear blade out of cutting engagement.

Another object of this invention is to provide a guide wheel having teeth, and a flat channelshaped guide plate resiliently pressed tangentially against the guide wheel to cause the wheel to lightly engage a belt loop strip being fed so as to guide the belt loop strip from the feed-dogs to the shear blades,

With the above and other objects in view, the invention will be hereinafter more particularly described, and the combination and arrangement of parts will be shown in the accompanying drawings and pointed out in the claims which form part of this specification.

Reference will now be had to the drawings, wherein like numerals of reference designate corresponding parts throughout the several views, in which:

Figure 1 is a top plan view of the strip cutting mechanism as applied to my belt loop sewing machine.

Figure 2 is a longitudinal sectional view, the section being taken as on line 2-2 in Figure 4.

Figure 3 is a longitudinal sectional elevation, the section being taken as on line 3-3 in Figure 4.

Figure 4 is an end elevation of the mechanism.

Figure 5 is a cross-sectional view, the section being taken as on line 5-5 in Figure 2.

Figure 6 is a rear view of the strip cutting mechanism.

Figure 7 is an end view, partly broken away to show a clutch mechanism.

Fi ure 8 is a side elevation showing two top side walls 21.

feed-dogs and a lower feed-dog used in the sewing machine for positive feeding.

Figure 9 is a longitudinal cross-sectional view,

porting base of a sewing machine comprising theusual standard H having a head (not shown) in which two spaced needles l2 and a looper cooperate to form interlock stitching. The material worked upon is held down by a presser-foot l3 resting on a needle plate ll secured to the work supporting base III. .The sewing machine relates to improvements whereby belt loops for trousers are automatically produced in a single operation by mechanism which cuts scraps of cloth into strips and folds said strips into belt loop form and .feeds said folded material with upper and lower feed-dogs. The sewing machine Ill makes stitched belt loop material in strip form and is fully disclosed in my patent application for Belt loop sewing machine, Serial No. 340,577, filed June 14, 1940, Patent Number 2,262,547. The present application relates to a mechanism l5 for cutting the belt strip into predetermined lengths.

The mechanism l5 comprises a housing I! having a shaft l'l rotatably mounted in bearings l8, IS. A guide wheel 20 having saw shaped teeth 2| has been fixed at one end of the shaft ll.

As best shown in Figures 2 and 3, I have provided an elongated guide plate 25 having a fiat upper work supporting surface 26 and upright The guide plate 25 extends into the housing 18 through an opening 28 in the front wall 29 and terminates at the inner face of the rear wall 30 in alinement with a rectangular opening 3| in said rear wall.

A plate 32 is fixed to one end portion of the housing It by a screw 33 and a pin 34. The plate 32 has through slots 35 and 36 providing passage therethrough for screws 31 and 33 extending outwardly from the guide plate 25. It will be seen that the guide plate 25 may be swung about its outer end 39 into and out of contact with a tangential point on the lower periphery of the guide wheel 20. A flanged bracket 40 fixed to the lower face of the housing l3 by bolts ll has an elongated opening for a coilspring 42. An adjusting nut 43 in the threaded lower end of the bracket 40 functions to raise the spring 4| in pressure contact with the guide plate 25 and forces the work supporting surface 23 of said plate in resilient engagement with the guide wheel 20.

The shear comprises a stationary blade ll fixed to the rear wall 80 of the housing It and having a horizontal cutting edge in alinement with the lower side of the rectangular opening 8|. A movable blade 4' has been mounted on a pivot 41 and is pressed into cutting engagement with the fixed blade 05 by a spring 08.

A reinforcing plate 4! has been mounted on the pivot 47 between the movable blade 46 and the spring 48. The plate 49 has a screw 80 threaded therein and contacting with the movable blade. The plate 49 servesfor causing a maximum pressure on the outermost point of the shear blades.-

The means for actuating the movable shear blade 48 may comprise a cam which is fixed on and rotated by the shaft II. The nose 56 of the cam 55 is positioned to face in the direction of the axis and parallel to the shaft H. A shear actuating lever 51 has been fixed to a rock shaft 50 slidably mounted in the housing It below the shaft II. The lever 01 has an arm 58 which has a movement parallel with the axis of-the shaft H. The free end of the arm 59 is disposed in the path of rotation of the nose B6 of the cam 55. The nose of the cam engages the free end of the arm 59 and causes a horizontally positioned shear actuating lever member 80 to rise. The lever member 60 has a slot 0| in engagement with the head of a screw 52 threaded into the noncutting end of the movable blade 40. Upward movement of the slotted end of the lever member 00 causes a swinging movement of the movable shear blade 00 into cutting engagement with the stationary shear blade.

The movable shear blade 46 is returned to its noncutting position, shown in Figure 6, as soon as the cam nose 58 moves away from under the free end SI of the arm 59. This swinging movement is accomplished by a spring 02, shown in Figure 6, which is housed in a cylindrical extension 03 at the upper elevation of the housing I. The spring 02 bears against the head 6! of an elongated rod mounted in the extension 63. A hollow threaded member i6 serves for adjusting the pressure of the head 64 against a square of the said lever in opposite directions. when the lever I0 is shifted to the right, the free end I of the arm 60 is brought out of the path of rotation of the nose 5! of the cam 55 and this movement causes the movable shear blade 48 to stay out of cutting engagement to permit the formation of long belt loop strips when desired.

The belt loop cutting mechanism herein described is particularly designed for cutting lengths of stitched belt loop strip fabric made from scrap material or pieces of fabric of various lengths. The disengaging feature of the movable shear blade is particularly desirable because it permits the operator to repeatedly throw the movable cutting blade into and out of operation. The operator is thus enabled to throw in the movable shear blade at any particular moment so as to start shearing substantially at the beginning of each length and thereby make amaximum number of belt loops from the particular strip having belt loop portions of unequal lengths.

Step-by-step rotation of the shaft I1 is synchronism with the feed-dogs of the sewing machine and the feed roller 20 is effected by a roller friction clutch 85. The clutch is actuated by an arm 88 and a pitman 81 having its lower end in engagement with an eccentric 80 on the main shaft 89 of the sewing machine.

A clutching detent carrier 95 is freely mounted for oscillation on the shaft II. The carrier 05 is also freely mounted within a casing 96 fixed to the shaft I1 by means of a screw 91 shown in Fi ure 2. A cover plate forming a continuation ofthe arm 06 is fastened to the clutching detent carrier 95.

In order to prevent reverse movement of the shaft I1, I have provided a braking detent carrier 08 freely mounted within the casing 96, as shown in Figure '7. The braking detent carrier 09 is integral with the bearing I9 and thus fixed to the housing I6. I

The clutch detent carrier 95 and the braking detent carrier 80 are mounted on the shaft II to work in opposite directions and may be in the shaped upper end portion 01 of an upright arm 00 of the lever 51 and forces the portion 01 of the lever arm 68 against 8. lug 08 formed on the housing I.

An important feature of the strip cutting mechanism I5 resides in means for at will shifting the lever 51 to bring the free end 8| of the arm 59 out of the path of rotation of the nose 50 of the cam 50 and the shear blade 40 out of cutting engagement. The shifting means comprises a shifting lever I5 rotatably mounted on'the rock shaft 58 and having a cam surface I8 angularly positioned with the axis of the rock shaft 50. A

' pin 11 fixed at one end of the rock shaft is in engagement with the cam surface 16. A spring I! on the shaft 50 and interposed between the front wall of the housing and the lever 51 holds the arms 59 in position for actuation by the cam, and

and thus raise and hold the movable shear blade '40 in noncutting position.

Pins III and GI projecting from the lower portion of the housing I0, on opposite sides of the shifting lever 15, serve to predetermine the throw form shown and described in Patent No. 1,985,400 issued to Nathan B. Galkin, dated December 25, 1934.

The clutch arm 86 has an arcuate slot I00 for receiving a screw II at the upper end of the pitman 81. One end of the screw I0l terminates in a ball-Jointed connection I02. A nut I03 on the screw IOI serves for clamping the screw II and the ball-jointed connection in any desired position along the length of the slot I00.

Attempts have been made to operate belt loop shearing mechanisms by driving connection from the feed rocker which normally forms part of the regular feeding mechanism of the sewing machine. It has however been found in practice that the said mechanism wears excessively and causes an overthrow and even breaks under the stresses imposed thereon'when shearing heavy fabric. I have found that an eccentric secured to the main shaft of the sewing machine is fully adapted to safely transmit the driving torque necessary for practical operating conditions.

Figure 9 shows a modified strip cutting mechanism I05 without any wheel on the shaft I00 and in which the shaft I00 terminates substantially at the outer face of the bearing I8. Figure 9 shows the shifting lever I5 and the shear actuating lever .51 moved so as to bring the free end 6| of the arm 59 out of the path of rotation of the nose 56 of the cam 05. It will be noted that the slotted lever member 60 has been moved into con.

tacting relation with the outer end of the screw head 52.

The modified strip cutting mechanism I05 has a shaft I06 which terminates at the outer end of the bearing I8. The movable blade 46 has been mounted on a pivot I01 and is held in cutting engagement with the fixed blade 45 by threaded nuts I08 and a washer I09.

Referring to Figures 1 and 8, it will be seen that the sewing machine to which the strip shearing mechanism is preferably applied, comprises a top feed-dog III! for feeding scrap fabric to duplex shear blades H5, a top feed-dog III for feeding trimmed fabric to and through a folder H2 and to the stitching mechanism. The top feed-dogs I I and II I are operated in timed relation with a lower feed-dog I I3. In practice, these three feeding devices have sufiicient power to feed all kinds of fabric without any necessity for a toothed wheel on the drive shaft of the loop cutting mechanism The type of cutting mechanism I5 having a guide wheel 2| is used when operating upon fabrics that are soft and fiufiy. The teeth 2| are saw-shaped, that is, each tooth has a side that is radially positioned and a side that makes an acute angle with the said radially positioned side. The type of cutting mechanism I05 is used when operating upon fabrics that have a degree of rigidity sufficient to maintain the straight line form of the strip I I6 being sheared.

For the purpose of adjusting the arm 86 in relation to the pitman 81, I have provided visible indicia II! on the upper face of the arm 86 whereby a pointer H8 on the pitman 81 may be used for adjustin the lengths to be out, such as 2% inches 3 inches, 3 inches, 4 inches, 4 inches, etc.

In accordance with the patent statutes, I have described and illustrated the preferred embodiment of my invention, but it will be understood that various changes and modifications can be made therein without departing from the spirit of the invention as defined by the appended claims.

I claim:

1. In a device for cutting strip fabric into pieces of predetermined lengths, comprising a shear, a rotary shear actuating shaft having a toothed wheel secured thereto for guiding said strip past said shear, said wheel secured thereto for guiding said strip past said shear, said wheel having teeth, a pivotally mounted guide plate having a flat and inclined upper surface for guiding said strip, means for resiliently contacting said guide plate and said strip with the rear portion of said wheel for engaging and guiding said strip, a lever actuating means carried by said shear actuating shaft for effecting actuation of said shear during each revolution of said'feed wheel, said actuating means in its entirety being non-movable relative to said shear actuating shaft, a lever one extremity of which swings in an arc in a direction substantially parallel to said shaft and being spring-pressed towards said lever actuating means, a further spring acting upon said lever to hold the same in operative engagement with said lever actuating means for transmitting motion from said lever actuating means to said shear, a clutch for actuatin said wheel, said guide plate being adapted for bringing said strip into contact with said wheel with a small pressure to permit slippage of said strip and means for at will relatively shifting said lever out of engagement with said lever actuating means during the operation of said machine to permit said spring further acting upon said lever to yieldingly hold said movable shear out of cutting engagement.

2. In a device for cutting positively fed strip fabric into pieces of predetermined length, comprising a shear, a shear actuating shaft having a toothed wheel secured thereto for guiding said strip past said shear, said wheel having teeth, a pivotally mounted guide plate having a flat and inclined upper surface and upright side walls providing a channel for guiding said strip, resilient means for bringing a fabric strip on said flat surface into contact with said wheel, for guiding said strip through said channel, an open face cam carried by said shear actuating shaft for effecting actuation of said shear during each revolution of said wheel, said open face cam in its entirety being non-movable relative to said shear actuating shaft, a lever one extremity of which swings in an arc in a direction substantially parallel to said shaft and being springpressed towards said cam, a further spring acting upon said lever to hold the same in operative engagement with said cam for transmitting motion from said shaft to said shear, a clutch for actuating said shaft and said wheel, said guide plate being adapted for bringing said strip into contact with said wheel with a small pressure to permit slippage of said strip, and means for at willrelatively shifting said lever out of engagement with said cam during operation of said machine to permit said spring further acting upon said lever to yieldingly hold said shear out of cutting engagement.

' JOSEPH GALKIN. 

